Hi
I have KX2 and I am using HyEnd Company Endfed 40/20/15/10 antenna most of the time
73 Thomas F4HPX
Hi Scott, I built it using plans from N4LQ, Steve Ellington. He has a Facebook group here: End Fed Half Wave Antennas | Facebook and some nice videos on youtube: https://www.youtube.com/user/n4lq/featured. The FT240 is sized for 100 Watts but for the QRP version, I used a smaller FT114 core with #22 AWG wire which doesn’t seem to saturate until 25-50 Watts so I could probably even go smaller.
My QRP version with strain relief -
Plans:
3 Likes
Fellow tree hugger here. I have a mental block about the name of what I use: I keep calling it embroidery thread but it’s UPHOLSTERY thread, cotton. It’s very light so I don’t think it could do any damage to a limb. The downside is that you either pull it very slowly or it breaks. I am still on the fence about whether getting the antenna end up this way is faster than the pole or not so I am at best a dabbler in this method.
FWIW there is also concern that reused antenna throwing line can be a vector for tree infestations. Michigan State Parks on the Air program specifically forbids hanging antennas in trees for this reason.
73,
Joe // N0MAP
1 Like
I have also built a number of wire antennas including a linked dipole. Here in the SE United States, the linked dipole is all but impossible to erect on summits because of the trees.
For a while I used the Sotabeams Bandskipper on the Sotabeams travel pole. It is a nice antenna that does a good job on my KX2. I still have it ready to use. However, I have gone to a resonant end-fed half wave connected to a 64:1 unun that I made. I take the 40m wire and counterpoise and usually work 40 and 20 well on it. For the small weight of the wires, I can take an assortment for whatever other bands I want to work. I actually cut a wire for 80m but I have not tried to deploy that monster yet. LOL
-Steve
W2SWA
Hi Steve (W2SWA),
Could you provide more details on the 64:1 unun and what lengths of counterpoise you use.
Counterpoises for resonant EFHW’s are usually 0.5 wavelengths but I’ve heard all kinds of lengths being used.
For the unun I’ve seen resonant tank circuits on the secondary and broadband transformers being used.
I am currently experimenting with a resonant tank circuit type as found in the SotaBeams Mountain Tuner but I’ve seen lots of designs for what I would call a broadband transformer like KJ4M has just posted.
Interested to understand what you are using…got any pics??
Thanks,
Paul VA6TTX
Sure, I have a buddy here locally (N1KDO) who has been using and liking this antenna setup with his KX3 for a while and has been encouraging me to give it a try. I finally built the unun pretty much exactly like he has on his website (link: https://www.n1kdo.com/baluns-ununs/index.html). It is the last thing on the page. I used a different case than he did, but it is pretty much the same otherwise. I made some small holes in the back of the case and looped a cable tie through it. Then I can velcro the cable tie to the pole, so it is not just hanging there. I dont have any pics of mine, but I will try to snap some next time I have it out.
The radiators are 0.5 wavelength and the counterpoise is 0.25 wavelength. The beauty of that is if you want to use the truly resonant wire for each band (and not have the tuner make up the difference) you can use/resuse wires as radiators and counterpoises. For example, the counterpoise for the 80m wire is the 40m radiator, the counterpoise for the 40m radiator can be used as the 20m radiator, and the 20m counterpoise can be the 10 radiator and so on. Same with 60/30/15. 17m and 12m are the only odd ducks that probably do best with their own set of wires. (I purposefully left out 6m since the KX2 doesnt have 6m :(. haha) So you can bring a whole “set” of wires out there and you will definitely have less than (# of bands)X2 sets of wires. Plus like I was saying before, the tuner can make up the difference as well. I did an activation a couple weeks ago, put the 40m set up, and did really well on both 40 and 20.
Hope that helps some.
-Steve
W2SWA
1 Like
Hi Steve.
Thanks for the response. You described your system very well so thanks for that.
I like the idea of using the wires for multiple purposes - that’s very creative and not something I would have though of!!
73,
Paul
I have used a couple of different antennas with my KX2. Nothing for SOTA activating yet, but some chasing on 5w and 10w and it’s worked very well.
For POTA and BOTA (Beaches) and just testing stuff in the back garden, I have used the following (I’ll probably be scoffed at for using COTS antennas but I’m still trying to learn making my own antennas with mixed success).
- Diamond RHM12 with optional RHMC12 and TRS3 - My current squeeze I use all the time. Obviously compromised but in my experience it works pretty much flawlessly. Covers all bands from 160m to 70cm - so for 2 and 70 i plug in my FT65. A joy to use but costs an absolute fortune. Saved up for it and imported from Japan direct to save about €100 on EU RRP even after taxes, duty etc. The RHM10 is available and a bit cheaper, but I always had my eye on the RHM12. Yer man Ramon (QRP CW on YouTube) uses one for SOTA with a 705 and has great success.
- JPC PAC-12 - Used this relentlessly from May 2024 to May 2025. Still in reasonable nick, though the ribbon cable for the radials snapped at the neck so I havent used it for a while. I got the RHM12 since so the PAC12 has been demoted. Always a joy to use though and with a little jiggery pokery you can get more than just 20 and 40 on it, aided as well by the KX2 ATU. Loads of mods available for this antenna too if you want to dig deeper. I’ll always have a soft spot for the PAC-12.
- Random wire to BNC banana plug thingy that costs about 7p on Amazon - As recommended by Nigel Mansell and it’s even mentioned by Elecraft in the KX2 manual as a recommended antenna! Made my own with some wire and a plug from Amazon and it works very well. I should use it more often. I’ve also made similar random wires with a LGC Unun in line and it seems to work too.
- Chameleon LEFS 8010 - This thing gets on my wick. Tried a couple of times to use it in a park and its just a pain in the hoop to set up. The fact it is green and ‘stealthy’ doesn’t help. Spend more time worrying someone will come running along and get decapitated off of it than actually operating it. Had it about a year and yet to successfully use it. I will though.
Hope the above is of some use. 
73.
2 Likes
When this thread was initiated I didn’t own my KX3, so the discussion was of no real interest. Talk on internal tuners was not something I associated with. Indeed I was a Yaesu FT-817 + link dipole man… or occasionally FT-857 + link dipole man.
Time moves on… Icom IC-703 with internal tuner was purchased. An HF linear had been added to the 817 set up. I initiated the Trans-Atlantic S2S events in 2016 and was now thinking verticals, initially for 20m and 17m. However some aspects of the station needed improvement. I added an LDG Auto-ATU for use with the linear… much more flexibility.
Time moving on again… FT-857 sold, KX3 purchased. Even more flexibility. So what of the set up with the KX3? If I am running barefoot, I find I prefer a 40m EFHW with counterpoise - this is the easiest solution with no getting up to change dipole links. Adding the linear certainly complicates things as the KX3 internal tuner can then only match the input to the linear. So I am either back to the link dipoles or the addition of the LDG tuner which is a complex set up. I therefore tend to deploy the KX3 without the linear.
As for the Trans-Atlantic events, the vertical has evolved. Finding a bit more oompf useful, I do use the KX3 with the linear, but now have a Slidewinder vertical to give me the flexibility on which bands are working. It works well, though I remain to be convinced that it is as good as a dipole or EFHW on 40m.
Although my KX3 is suitably housed to protect it from the damp, if the weather conditions on the summit are likely to be dire, I do tend to use my 817 as the risk to my investment in radio kit is somewhat lower. I operate the 817 from within the backpack. It’s a matter of ergonomics.
Mr Untidy on Hergest Ridge G/WB-008 in 2023.
Edit: Following on from the post by Andy G8CPZ, I realised that I have never ever considered anything like a Cameleon MPAS vertical or any antenna by MFJ. Such products are not on my radar. The addition of the Slidewinder was after learning that Carl 2E0HPI had great success with the antenna. Even so, I just couldn’t bring myself to buy the whip or counterpoise wires. My version is mast mounted and uses 12 gauge flexible wire for the vertical element.
Mr Cheapskate’s Slidewinder mast mounted vertical.
3 Likes
You didn’t specifically mention whether or not your KX2 has the internal ATU, KXAT2, but, from the title, I assume you have it or an external one. KX2 owners (like me) are always rightly going on about how brilliant its ATU is. Some say it could probably load up a wire fence should you forget to pack your antenna and no doubt the proverbial wet piece of string too.
But, to answer your question, my HF antennas are a mixture of branded/purchased, modified branded and homemade.
The main ones used with my KX2 are:
- centre-fed 80/60m & 60/40/30/20m linked dipoles
- 40/30/20m & 40/20/10m EFHWs
- Chameleon MPAS Lite 40-10m vertical
- For ‘minimalist’ activations: MFJ-1830 and MFJ-1817 138-cm-long monoband telescoping whips on homemade bipod mounting bracket, plus a 7m counterpoise wire.
Choice on the day depends on:
- the band(s) to be worked
- summit topology (e.g. flat & spacious vs outcrops/rocky/confined/crowded with people)
- ground conditions (e.g. solid rock vs grassy with deep soil)
- weather (e.g. high winds / heavy rain vs calm / dry).
Many of the summits I activate are solid rock in the AZ or with very little top soil making it hard or impossible to get the guying pegs in the ground properly and my Life’s a Breeze 6m telescopic pole not to fall over in a gust of wind.
If bad weather or where a small footprint is needed, I take the MPAS Lite which is very robust, otherwise it’s a wire antenna. The default choice is the 40/30/20m EFHW (usually configured as inverted-L if lucky, inverted-7 otherwise).
3 Likes
Wow, it’s been seven years since l posted here.
I’ve been using an EFHW that connects directly onto my KX2 for five years now. Dipoles are retired.
Malen
VE6VID
4 Likes
My go to radio and antenna has been my KX2 with a W1SFR KX3 End fed 40-6 meters. This antenna has worked fantastic for me. The antenna is currently unavailable, but very easy to make. Here a great link: End Fed 40-6M Antenna and Kit | W1SFR Handmade Torsion Bar Morse Code Keys
2 Likes
I used an OM0ET 49:1 with silicone wire I think it may be 43’ long.
1 Like
Well, I think we can conclude after 7 years and dozens of different antennas identified from KX2(3) owners, that these rigs (with int. ATU) work very well with any decent antenna.
1 Like
The KX2 ATU could tune a blob of ice cream 1:1 on top band. 
Have you tried it? [tee hee]
A bit of chocolate from a Magnum fell off near it once. I didn’t check to see if it could tune it but the noise floor on 20m dropped significantly at the same time.
Coincidence? 
1 Like
I have a 50 ohm resistor that’s a 1:1 SWR on all bands and I don’t even need an ATU.
2 Likes
Even when it’s more than a wavelength? 
That’s better than mine Richard. On mine the SWR is 1.1:1 above 1GHz.
1 Like